Re: [PATCH v8 2/8] hwtracing: hisi_ptt: Add trace function support for HiSilicon PCIe Tune and Trace device

[John Garry <john.garry@huawei.com>]

On 16/05/2022 13:52, Yicong Yang wrote:
> HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
> Endpoint(RCiEP) device, providing the capability to dynamically monitor and
> tune the PCIe traffic and trace the TLP headers.
> 
> Add the driver for the device to enable the trace function. Register PMU
> device of PTT trace, then users can use trace through perf command. The
> driver makes use of perf AUX trace function and support the following
> events to configure the trace:
> 
> - filter: select Root port or Endpoint to trace
> - type: select the type of traced TLP headers
> - direction: select the direction of traced TLP headers
> - format: select the data format of the traced TLP headers
> 
> This patch initially add a basic driver of PTT trace.

Initially add basic trace support.

> 
> Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>

Generally this looks ok, apart from nitpicking below, so, FWIW:
Reviewed-by: John Garry <john.garry@huawei.com>

> ---
>   drivers/Makefile                 |   1 +
>   drivers/hwtracing/Kconfig        |   2 +
>   drivers/hwtracing/ptt/Kconfig    |  12 +
>   drivers/hwtracing/ptt/Makefile   |   2 +
>   drivers/hwtracing/ptt/hisi_ptt.c | 964 +++++++++++++++++++++++++++++++
>   drivers/hwtracing/ptt/hisi_ptt.h | 178 ++++++
>   6 files changed, 1159 insertions(+)
>   create mode 100644 drivers/hwtracing/ptt/Kconfig
>   create mode 100644 drivers/hwtracing/ptt/Makefile
>   create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
>   create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
> 
> diff --git a/drivers/Makefile b/drivers/Makefile
> index 020780b6b4d2..662d50599467 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -175,6 +175,7 @@ obj-$(CONFIG_USB4)		+= thunderbolt/
>   obj-$(CONFIG_CORESIGHT)		+= hwtracing/coresight/
>   obj-y				+= hwtracing/intel_th/
>   obj-$(CONFIG_STM)		+= hwtracing/stm/
> +obj-$(CONFIG_HISI_PTT)		+= hwtracing/ptt/
>   obj-$(CONFIG_ANDROID)		+= android/
>   obj-$(CONFIG_NVMEM)		+= nvmem/
>   obj-$(CONFIG_FPGA)		+= fpga/
> diff --git a/drivers/hwtracing/Kconfig b/drivers/hwtracing/Kconfig
> index 13085835a636..911ee977103c 100644
> --- a/drivers/hwtracing/Kconfig
> +++ b/drivers/hwtracing/Kconfig
> @@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
>   
>   source "drivers/hwtracing/intel_th/Kconfig"
>   
> +source "drivers/hwtracing/ptt/Kconfig"
> +
>   endmenu
> diff --git a/drivers/hwtracing/ptt/Kconfig b/drivers/hwtracing/ptt/Kconfig
> new file mode 100644
> index 000000000000..6d46a09ffeb9
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Kconfig
> @@ -0,0 +1,12 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config HISI_PTT
> +	tristate "HiSilicon PCIe Tune and Trace Device"
> +	depends on ARM64 || (COMPILE_TEST && 64BIT)
> +	depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
> +	help
> +	  HiSilicon PCIe Tune and Trace device exists as a PCIe RCiEP
> +	  device, and it provides support for PCIe traffic tuning and
> +	  tracing TLP headers to the memory.
> +
> +	  This driver can also be built as a module. If so, the module
> +	  will be called hisi_ptt.
> diff --git a/drivers/hwtracing/ptt/Makefile b/drivers/hwtracing/ptt/Makefile
> new file mode 100644
> index 000000000000..908c09a98161
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_HISI_PTT) += hisi_ptt.o
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
> new file mode 100644
> index 000000000000..ef25ce98f664
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.c
> @@ -0,0 +1,964 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <yangyicong@hisilicon.com>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/cpuhotplug.h>
> +#include <linux/delay.h>
> +#include <linux/dma-iommu.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/iommu.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/sysfs.h>
> +#include <linux/vmalloc.h>
> +
> +#include "hisi_ptt.h"
> +
> +/* Dynamic CPU hotplug state used by PTT */
> +static enum cpuhp_state hisi_ptt_pmu_online;
> +
> +static u16 hisi_ptt_get_filter_val(u16 devid, bool is_port)
> +{
> +	if (is_port)
> +		return BIT(HISI_PCIE_CORE_PORT_ID(devid & 0xff));
> +
> +	return devid;
> +}
> +
> +static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
> +{
> +	u32 val;
> +
> +	return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
> +					  val, val & HISI_PTT_TRACE_IDLE,
> +					  HISI_PTT_WAIT_POLL_INTERVAL_US,
> +					  HISI_PTT_WAIT_TRACE_TIMEOUT_US);
> +}
> +
> +static void hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
> +{
> +	u32 val;
> +
> +	readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
> +				  val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
> +				  HISI_PTT_RESET_TIMEOUT_US);
> +}
> +
> +static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
> +{
> +	writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +	hisi_ptt->trace_ctrl.started = false;
> +}
> +
> +static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
> +{
> +	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> +	u32 val;
> +	int i;
> +
> +	/* Check device idle before start trace */
> +	if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
> +		pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
> +		return -EBUSY;
> +	}
> +
> +	ctrl->started = true;
> +
> +	/* Reset the DMA before start tracing */
> +	val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +	val |= HISI_PTT_TRACE_CTRL_RST;
> +	writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> +	hisi_ptt_wait_dma_reset_done(hisi_ptt);
> +
> +	val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +	val &= ~HISI_PTT_TRACE_CTRL_RST;
> +	writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> +	/* Reset the index of current buffer */
> +	hisi_ptt->trace_ctrl.buf_index = 0;
> +
> +	/* Zero the trace buffers */
> +	for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
> +		memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
> +
> +	/* Clear the interrupt status */
> +	writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> +	writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
> +
> +	/* Set the trace control register */
> +	val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
> +	val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
> +	val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
> +	val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
> +	if (!hisi_ptt->trace_ctrl.is_port)
> +		val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
> +
> +	/* Start the Trace */
> +	val |= HISI_PTT_TRACE_CTRL_EN;
> +	writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> +	return 0;
> +}
> +
> +static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
> +{
> +	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> +	struct perf_output_handle *handle = &ctrl->handle;
> +	struct perf_event *event = handle->event;
> +	struct hisi_ptt_pmu_buf *buf;
> +	size_t size;
> +	void *addr;
> +
> +	buf = perf_get_aux(handle);
> +	if (!buf || !handle->size)
> +		return -EINVAL;
> +
> +	addr = ctrl->trace_buf[ctrl->buf_index].addr;
> +
> +	/*
> +	 * If we're going to stop, read the size of already traced data from
> +	 * HISI_PTT_TRACE_WR_STS. Otherwise we're coming from the interrupt,
> +	 * the data size is always HISI_PTT_TRACE_BUF_SIZE.
> +	 */
> +	if (stop) {
> +		u32 reg;
> +
> +		reg = readl(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS);
> +		size = FIELD_GET(HISI_PTT_TRACE_WR_STS_WRITE, reg);
> +	} else {
> +		size = HISI_PTT_TRACE_BUF_SIZE;
> +	}
> +
> +	memcpy(buf->base + buf->pos, addr, size);
> +	buf->pos += size;
> +
> +	/*
> +	 * Just commit the traced data if we're going to stop. Otherwise if the
> +	 * resident AUX buffer cannot contain the data of next trace buffer,
> +	 * apply a new one.
> +	 */
> +	if (stop) {
> +		perf_aux_output_end(handle, buf->pos);
> +	} else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> +		perf_aux_output_end(handle, buf->pos);
> +
> +		buf = perf_aux_output_begin(handle, event);
> +		if (!buf)
> +			return -EINVAL;
> +
> +		buf->pos = handle->head % buf->length;
> +		if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> +			perf_aux_output_end(handle, 0);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
> +static irqreturn_t hisi_ptt_isr(int irq, void *context)
> +{
> +	struct hisi_ptt *hisi_ptt = context;
> +	u32 status, buf_idx;
> +
> +	status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> +	if (!(status & HISI_PTT_TRACE_INT_STAT_MASK))
> +		return IRQ_NONE;
> +
> +	buf_idx = ffs(status) - 1;
> +
> +	/* Clear the interrupt status of buffer @buf_idx */
> +	writel(status, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> +
> +	/*
> +	 * Update the AUX buffer and cache the current buffer index,
> +	 * as we need to know this and save the data when the trace
> +	 * is ended out of the interrupt handler. End the trace
> +	 * if the updating fails.
> +	 */
> +	if (hisi_ptt_update_aux(hisi_ptt, buf_idx, false))
> +		hisi_ptt_trace_end(hisi_ptt);
> +	else
> +		hisi_ptt->trace_ctrl.buf_index = (buf_idx + 1) % HISI_PTT_TRACE_BUF_CNT;
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void hisi_ptt_irq_free_vectors(void *pdev)
> +{
> +	pci_free_irq_vectors(pdev);
> +}
> +
> +static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
> +{
> +	struct pci_dev *pdev = hisi_ptt->pdev;
> +	int ret;
> +
> +	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
> +	if (ret < 0) {
> +		pci_err(pdev, "failed to allocate irq vector, ret = %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_irq_free_vectors, pdev);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = devm_request_threaded_irq(&pdev->dev,
> +					pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ),
> +					NULL, hisi_ptt_isr, 0,
> +					DRV_NAME, hisi_ptt);
> +	if (ret) {
> +		pci_err(pdev, "failed to request irq %d, ret = %d\n",
> +			pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
> +{
> +	struct hisi_ptt_filter_desc *filter;
> +	struct hisi_ptt *hisi_ptt = data;
> +
> +	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
> +	if (!filter) {
> +		pci_err(hisi_ptt->pdev, "failed to add filter %s\n", pci_name(pdev));
> +		return -ENOMEM;
> +	}
> +
> +	filter->devid = PCI_DEVID(pdev->bus->number, pdev->devfn);
> +
> +	if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT) {
> +		filter->is_port = true;
> +		list_add_tail(&filter->list, &hisi_ptt->port_filters);
> +
> +		/* Update the available port mask */
> +		hisi_ptt->port_mask |= hisi_ptt_get_filter_val(filter->devid, true);
> +	} else {
> +		list_add_tail(&filter->list, &hisi_ptt->req_filters);
> +	}
> +
> +	return 0;
> +}
> +
> +static void hisi_ptt_release_filters(void *data)
> +{
> +	struct hisi_ptt_filter_desc *filter, *tmp;
> +	struct hisi_ptt *hisi_ptt = data;
> +
> +	list_for_each_entry_safe(filter, tmp, &hisi_ptt->req_filters, list) {
> +		list_del(&filter->list);
> +		kfree(filter);
> +	}
> +
> +	list_for_each_entry_safe(filter, tmp, &hisi_ptt->port_filters, list) {
> +		list_del(&filter->list);
> +		kfree(filter);
> +	}
> +}
> +
> +static int hisi_ptt_config_trace_buf(struct hisi_ptt *hisi_ptt)
> +{
> +	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> +	struct device *dev = &hisi_ptt->pdev->dev;
> +	int i;
> +
> +	ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
> +				       sizeof(*ctrl->trace_buf), GFP_KERNEL);
> +	if (!ctrl->trace_buf)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
> +		ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
> +							     &ctrl->trace_buf[i].dma,
> +							     GFP_KERNEL);
> +		if (!ctrl->trace_buf[i].addr)
> +			return -ENOMEM;
> +	}
> +
> +	/* Configure the trace DMA buffer */
> +	for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
> +		writel(lower_32_bits(ctrl->trace_buf[i].dma),
> +		       hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
> +		       i * HISI_PTT_TRACE_ADDR_STRIDE);
> +		writel(upper_32_bits(ctrl->trace_buf[i].dma),
> +		       hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
> +		       i * HISI_PTT_TRACE_ADDR_STRIDE);
> +	}
> +	writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
> +
> +	return 0;
> +}
> +
> +static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
> +{
> +	struct pci_dev *pdev = hisi_ptt->pdev;
> +	struct pci_bus *bus;
> +	int ret;
> +	u32 reg;
> +
> +	INIT_LIST_HEAD(&hisi_ptt->port_filters);
> +	INIT_LIST_HEAD(&hisi_ptt->req_filters);
> +
> +	ret = hisi_ptt_config_trace_buf(hisi_ptt);
> +	if (ret)
> +		return ret;
> +
> +	/*
> +	 * The device range register provides the information about the
> +	 * root ports which the RCiEP can control and trace. The RCiEP
> +	 * and the root ports it support are on the same PCIe core, with

  ports which it supports are on the same ..

> +	 * same domain number but maybe different bus number. The device
> +	 * range register will tell us which root ports we can support,
> +	 * Bit[31:16] indicates the upper BDF numbers of the root port,
> +	 * while Bit[15:0] indicates the lower.
> +	 */
> +	reg = readl(hisi_ptt->iobase + HISI_PTT_DEVICE_RANGE);
> +	hisi_ptt->upper_bdf = FIELD_GET(HISI_PTT_DEVICE_RANGE_UPPER, reg);
> +	hisi_ptt->lower_bdf = FIELD_GET(HISI_PTT_DEVICE_RANGE_LOWER, reg);
> +
> +	bus = pci_find_bus(pci_domain_nr(pdev->bus), PCI_BUS_NUM(hisi_ptt->upper_bdf));
> +	if (bus)
> +		pci_walk_bus(bus, hisi_ptt_init_filters, hisi_ptt);
> +
> +	ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_release_filters, hisi_ptt);
> +	if (ret)
> +		return ret;
> +
> +	hisi_ptt->trace_ctrl.on_cpu = -1;
> +	return 0;
> +}
> +
> +static ssize_t available_root_port_filters_show(struct device *dev,
> +						struct device_attribute *attr,
> +						char *buf)
> +{
> +	struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> +	struct hisi_ptt_filter_desc *filter;
> +	int pos = 0;
> +
> +	if (list_empty(&hisi_ptt->port_filters)) {
> +		pos = sysfs_emit(buf, "\n");
> +		goto out;
> +	}
> +
> +	list_for_each_entry(filter, &hisi_ptt->port_filters, list) {
> +		u16 devid = filter->devid;
> +		pos += sysfs_emit_at(buf, pos, "%04x:%02x:%02x.%d\t0x%05lx\n",
> +				     pci_domain_nr(hisi_ptt->pdev->bus),
> +				     PCI_BUS_NUM(devid),
> +				     PCI_SLOT(devid & 0xff),
> +				     PCI_FUNC(devid & 0xff),
> +				     hisi_ptt_get_filter_val(devid, true) |
> +				     HISI_PTT_PMU_FILTER_IS_PORT);
> +	}
> +
> +out:
> +	return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_root_port_filters);
> +
> +static ssize_t available_requester_filters_show(struct device *dev,
> +						struct device_attribute *attr,
> +						char *buf)
> +{
> +	struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> +	struct hisi_ptt_filter_desc *filter;
> +	int pos = 0;
> +
> +	if (list_empty(&hisi_ptt->req_filters)) {
> +		pos = sysfs_emit(buf, "\n");
> +		goto out;

nit: return immediately

> +	}
> +
> +	list_for_each_entry(filter, &hisi_ptt->req_filters, list) {
> +		u16 devid = filter->devid;
> +		pos += sysfs_emit_at(buf, pos, "%04x:%02x:%02x.%d\t0x%05x\n",
> +				     pci_domain_nr(hisi_ptt->pdev->bus),
> +				     PCI_BUS_NUM(devid),
> +				     PCI_SLOT(devid & 0xff),
> +				     PCI_FUNC(devid & 0xff),
> +				     hisi_ptt_get_filter_val(devid, false));
> +	}
> +
> +out:
> +	return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_requester_filters);
> +
> +static ssize_t cpumask_show(struct device *dev, struct device_attribute *attr,
> +			    char *buf)
> +{
> +	struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> +	const cpumask_t *cpumask = cpumask_of_node(dev_to_node(&hisi_ptt->pdev->dev));
> +
> +	return cpumap_print_to_pagebuf(true, buf, cpumask);
> +}
> +static DEVICE_ATTR_RO(cpumask);
> +
> +static struct attribute *hisi_ptt_cpumask_attrs[] = {
> +	&dev_attr_cpumask.attr,
> +	NULL,

nit: no need to ',' on sentinel

> +};
> +
> +static const struct attribute_group hisi_ptt_cpumask_attr_group = {
> +	.attrs = hisi_ptt_cpumask_attrs,
> +};
> +
> +PMU_FORMAT_ATTR(filter,		"config:0-19");
> +PMU_FORMAT_ATTR(direction,	"config:20-23");
> +PMU_FORMAT_ATTR(type,		"config:24-31");
> +PMU_FORMAT_ATTR(format,		"config:32-35");
> +
> +static struct attribute *hisi_ptt_pmu_format_attrs[] = {
> +	&format_attr_filter.attr,
> +	&format_attr_direction.attr,
> +	&format_attr_type.attr,
> +	&format_attr_format.attr,
> +	NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_format_group = {
> +	.name = "format",
> +	.attrs = hisi_ptt_pmu_format_attrs,
> +};
> +
> +static struct attribute *hisi_ptt_pmu_filter_attrs[] = {
> +	&dev_attr_available_root_port_filters.attr,
> +	&dev_attr_available_requester_filters.attr,
> +	NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_filter_group = {
> +	.attrs = hisi_ptt_pmu_filter_attrs,
> +};
> +
> +static const struct attribute_group *hisi_ptt_pmu_groups[] = {
> +	&hisi_ptt_cpumask_attr_group,
> +	&hisi_ptt_pmu_format_group,
> +	&hisi_ptt_pmu_filter_group,
> +	NULL
> +};
> +
> +static int hisi_ptt_trace_valid_direction(u32 val)
> +{
> +	/*
> +	 * The supported value of the direction parameter. See hisi_ptt.rst
> +	 * documentation for more details.
> +	 */
> +	static const u32 hisi_ptt_trace_available_direction[] = {
> +		0,
> +		1,
> +		2,
> +		3,
> +	};
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_available_direction); i++) {
> +		if (val == hisi_ptt_trace_available_direction[i])
> +			return 0;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int hisi_ptt_trace_valid_type(u32 val)
> +{
> +	/* Different types can be set simultaneously */
> +	static const u32 hisi_ptt_trace_available_type[] = {
> +		1,	/* posted_request */
> +		2,	/* non-posted_request */
> +		4,	/* completion */
> +	};
> +	int i;
> +
> +	if (!val)
> +		return -EINVAL;
> +
> +	/*
> +	 * Walk the available list and clear the valid bits of
> +	 * the config. If there is any resident bit after the
> +	 * walk then the config is invalid.
> +	 */
> +	for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_available_type); i++)
> +		val &= ~hisi_ptt_trace_available_type[i];
> +
> +	if (val)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
> +static int hisi_ptt_trace_valid_format(u32 val)
> +{
> +	static const u32 hisi_ptt_trace_availble_format[] = {
> +		0,	/* 4DW */
> +		1,	/* 8DW */
> +	};
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(hisi_ptt_trace_availble_format); i++) {
> +		if (val == hisi_ptt_trace_availble_format[i])
> +			return 0;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static int hisi_ptt_trace_valid_filter(struct hisi_ptt *hisi_ptt, u64 config)
> +{
> +	unsigned long val, port_mask = hisi_ptt->port_mask;
> +	struct hisi_ptt_filter_desc *filter;
> +	int ret = -EINVAL;
> +
> +	hisi_ptt->trace_ctrl.is_port = FIELD_GET(HISI_PTT_PMU_FILTER_IS_PORT, config);
> +	val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, config);
> +
> +	/*
> +	 * Port filters are defined as bit mask. For port filters, check
> +	 * the bits in the @val are within the range of hisi_ptt->port_mask
> +	 * and whether it's empty or not, otherwise user has specified
> +	 * some unsupported root ports.
> +	 *
> +	 * For Requester ID filters, walk the available filter list to see
> +	 * whether we have one matched.
> +	 */
> +	if (!hisi_ptt->trace_ctrl.is_port) {
> +		list_for_each_entry(filter, &hisi_ptt->req_filters, list) {
> +			if (val == hisi_ptt_get_filter_val(filter->devid, filter->is_port)) {
> +				ret = 0;
> +				break;
> +			}
> +		}
> +	} else if (bitmap_subset(&val, &port_mask, BITS_PER_LONG)) {
> +		ret = 0;
> +	}
> +
> +	if (ret)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +static void hisi_ptt_pmu_init_configs(struct hisi_ptt *hisi_ptt, struct perf_event *event)
> +{
> +	struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> +	u32 val;
> +
> +	val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, event->attr.config);
> +	hisi_ptt->trace_ctrl.filter = val;
> +
> +	val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
> +	ctrl->direction = val;
> +
> +	val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
> +	ctrl->type = val;
> +
> +	val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
> +	ctrl->format = val;
> +}
> +
> +static int hisi_ptt_pmu_event_init(struct perf_event *event)
> +{
> +	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> +	int ret;
> +	u32 val;
> +
> +	if (event->cpu < 0) {
> +		dev_dbg(event->pmu->dev, "Per-task mode not supported\n");
> +		return -EOPNOTSUPP;
> +	}
> +
> +	if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
> +		return -ENOENT;
> +
> +	ret = hisi_ptt_trace_valid_filter(hisi_ptt, event->attr.config);
> +	if (ret < 0)
> +		return ret;
> +
> +	val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
> +	ret = hisi_ptt_trace_valid_direction(val);
> +	if (ret < 0)
> +		return ret;
> +
> +	val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
> +	ret = hisi_ptt_trace_valid_type(val);
> +	if (ret < 0)
> +		return ret;
> +
> +	val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
> +	ret = hisi_ptt_trace_valid_format(val);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
> +				    int nr_pages, bool overwrite)
> +{
> +	struct hisi_ptt_pmu_buf *buf;
> +	struct page **pagelist;
> +	int i;
> +
> +	if (overwrite) {
> +		dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
> +		return NULL;
> +	}
> +
> +	/* If the pages size less than buffers, we cannot start trace */
> +	if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
> +		return NULL;
> +
> +	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
> +	if (!buf)
> +		return NULL;
> +
> +	pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
> +	if (!pagelist)
> +		goto err;
> +
> +	for (i = 0; i < nr_pages; i++)
> +		pagelist[i] = virt_to_page(pages[i]);
> +
> +	buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
> +	if (!buf->base) {
> +		kfree(pagelist);
> +		goto err;
> +	}
> +
> +	buf->nr_pages = nr_pages;
> +	buf->length = nr_pages * PAGE_SIZE;
> +	buf->pos = 0;
> +
> +	kfree(pagelist);
> +	return buf;
> +err:
> +	kfree(buf);
> +	return NULL;
> +}
> +
> +static void hisi_ptt_pmu_free_aux(void *aux)
> +{
> +	struct hisi_ptt_pmu_buf *buf = aux;
> +
> +	vunmap(buf->base);
> +	kfree(buf);
> +}
> +
> +static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
> +{
> +	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> +	struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
> +	struct hw_perf_event *hwc = &event->hw;
> +	struct device *dev = event->pmu->dev;
> +	struct hisi_ptt_pmu_buf *buf;
> +	int cpu = event->cpu;
> +	int ret;
> +
> +	hwc->state = 0;
> +
> +	/* Serialize the perf process if user specified several CPUs */
> +	spin_lock(&hisi_ptt->pmu_lock);
> +	if (hisi_ptt->trace_ctrl.started) {
> +		dev_dbg(dev, "trace has already started\n");
> +		goto stop;
> +	}
> +
> +	/*
> +	 * Handle the interrupt on the same cpu which starts the trace to avoid
> +	 * context mismatch. Otherwise we'll trigger the WARN from the perf
> +	 * core in event_function_local().
> +	 */
> +	WARN_ON(irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
> +				 cpumask_of(cpu)));
> +	hisi_ptt->trace_ctrl.on_cpu = cpu;
> +
> +	buf = perf_aux_output_begin(handle, event);
> +	if (!buf) {
> +		dev_dbg(dev, "aux output begin failed\n");
> +		goto stop;
> +	}
> +
> +	buf->pos = handle->head % buf->length;
> +
> +	hisi_ptt_pmu_init_configs(hisi_ptt, event);
> +
> +	ret = hisi_ptt_trace_start(hisi_ptt);
> +	if (ret) {
> +		dev_dbg(dev, "trace start failed, ret = %d\n", ret);
> +		perf_aux_output_end(handle, 0);
> +		goto stop;
> +	}
> +
> +	spin_unlock(&hisi_ptt->pmu_lock);
> +	return;
> +stop:
> +	event->hw.state |= PERF_HES_STOPPED;
> +	spin_unlock(&hisi_ptt->pmu_lock);
> +}
> +
> +static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
> +{
> +	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> +	struct hw_perf_event *hwc = &event->hw;
> +
> +	if (hwc->state & PERF_HES_STOPPED)
> +		return;
> +
> +	spin_lock(&hisi_ptt->pmu_lock);
> +	if (hisi_ptt->trace_ctrl.started) {
> +		hisi_ptt_trace_end(hisi_ptt);
> +		WARN(!hisi_ptt_wait_trace_hw_idle(hisi_ptt), "Device is still busy");
> +		hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
> +	}
> +	spin_unlock(&hisi_ptt->pmu_lock);
> +
> +	hwc->state |= PERF_HES_STOPPED;
> +	perf_event_update_userpage(event);
> +	hwc->state |= PERF_HES_UPTODATE;
> +}
> +
> +static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
> +{
> +	struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> +	struct hw_perf_event *hwc = &event->hw;
> +	int cpu = event->cpu;
> +
> +	/* Only allow the cpus on the device's node to add the event */
> +	if (!cpumask_test_cpu(cpu, cpumask_of_node(dev_to_node(&hisi_ptt->pdev->dev))))
> +		return 0;
> +
> +	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
> +
> +	if (flags & PERF_EF_START) {
> +		hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
> +		if (hwc->state & PERF_HES_STOPPED)
> +			return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
> +{
> +	hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
> +}
> +
> +static void hisi_ptt_remove_cpuhp_instance(void *hotplug_node)
> +{
> +	cpuhp_state_remove_instance(hisi_ptt_pmu_online, hotplug_node);
> +}
> +
> +static void hisi_ptt_unregister_pmu(void *pmu)
> +{
> +	perf_pmu_unregister(pmu);
> +}
> +
> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
> +{
> +	u16 core_id, sicl_id;
> +	char *pmu_name;
> +	u32 reg;
> +	int ret;
> +
> +	ret = cpuhp_state_add_instance(hisi_ptt_pmu_online, &hisi_ptt->hotplug_node);
> +	if (ret)
> +		return ret;
> +
> +	ret = devm_add_action_or_reset(&hisi_ptt->pdev->dev,
> +				       hisi_ptt_remove_cpuhp_instance,
> +				       &hisi_ptt->hotplug_node);
> +	if (ret)
> +		return ret;
> +
> +	spin_lock_init(&hisi_ptt->pmu_lock);
> +
> +	hisi_ptt->hisi_ptt_pmu = (struct pmu) {
> +		.module		= THIS_MODULE,
> +		.capabilities	= PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
> +		.task_ctx_nr	= perf_sw_context,
> +		.attr_groups	= hisi_ptt_pmu_groups,
> +		.event_init	= hisi_ptt_pmu_event_init,
> +		.setup_aux	= hisi_ptt_pmu_setup_aux,
> +		.free_aux	= hisi_ptt_pmu_free_aux,
> +		.start		= hisi_ptt_pmu_start,
> +		.stop		= hisi_ptt_pmu_stop,
> +		.add		= hisi_ptt_pmu_add,
> +		.del		= hisi_ptt_pmu_del,
> +	};
> +
> +	reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
> +	core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
> +	sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
> +
> +	pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
> +				  sicl_id, core_id);
> +	if (!pmu_name)
> +		return -ENOMEM;
> +
> +	ret = perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
> +	if (ret)
> +		return ret;
> +
> +	return devm_add_action_or_reset(&hisi_ptt->pdev->dev,
> +					hisi_ptt_unregister_pmu,
> +					&hisi_ptt->hisi_ptt_pmu);
> +}
> +
> +/*
> + * The DMA of PTT trace can only use direct mapping, due to some

nit: drop ',' and use "mappings"

> + * hardware restriction. Check whether there is an IOMMU or the
> + * policy of the IOMMU domain is passthrough, otherwise the trace
> + * cannot work.
> + *
> + * The PTT device is supposed to behind an ARM SMMUv3, which
> + * should have passthrough the device by a quirk.
> + */
> +static int hisi_ptt_check_iommu_mapping(struct pci_dev *pdev)
> +{
> +	struct iommu_domain *iommu_domain;
> +
> +	iommu_domain = iommu_get_domain_for_dev(&pdev->dev);
> +	if (!iommu_domain || iommu_domain->type == IOMMU_DOMAIN_IDENTITY)
> +		return 0;
> +
> +	return -EOPNOTSUPP;
> +}
> +
> +static int hisi_ptt_probe(struct pci_dev *pdev,
> +			  const struct pci_device_id *id)
> +{
> +	struct hisi_ptt *hisi_ptt;
> +	int ret;
> +
> +	ret = hisi_ptt_check_iommu_mapping(pdev);
> +	if (ret) {
> +		pci_err(pdev, "requires direct DMA mappings\n");
> +		return ret;
> +	}
> +
> +	hisi_ptt = devm_kzalloc(&pdev->dev, sizeof(*hisi_ptt), GFP_KERNEL);
> +	if (!hisi_ptt)
> +		return -ENOMEM;
> +
> +	hisi_ptt->pdev = pdev;
> +	pci_set_drvdata(pdev, hisi_ptt);
> +
> +	ret = pcim_enable_device(pdev);
> +	if (ret) {
> +		pci_err(pdev, "failed to enable device, ret = %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = pcim_iomap_regions(pdev, BIT(2), DRV_NAME);
> +	if (ret) {
> +		pci_err(pdev, "failed to remap io memory, ret = %d\n", ret);
> +		return ret;
> +	}
> +
> +	hisi_ptt->iobase = pcim_iomap_table(pdev)[2];
> +
> +	ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
> +	if (ret) {
> +		pci_err(pdev, "failed to set 64 bit dma mask, ret = %d\n", ret);
> +		return ret;
> +	}
> +
> +	pci_set_master(pdev);
> +
> +	ret = hisi_ptt_register_irq(hisi_ptt);
> +	if (ret)
> +		return ret;
> +
> +	ret = hisi_ptt_init_ctrls(hisi_ptt);
> +	if (ret) {
> +		pci_err(pdev, "failed to init controls, ret = %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = hisi_ptt_register_pmu(hisi_ptt);
> +	if (ret) {
> +		pci_err(pdev, "failed to register PMU device, ret = %d", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct pci_device_id hisi_ptt_id_tbl[] = {
> +	{ PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12e) },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(pci, hisi_ptt_id_tbl);
> +
> +static struct pci_driver hisi_ptt_driver = {
> +	.name = DRV_NAME,
> +	.id_table = hisi_ptt_id_tbl,
> +	.probe = hisi_ptt_probe,
> +};
> +
> +static int hisi_ptt_cpu_teardown(unsigned int cpu, struct hlist_node *node)
> +{
> +	struct hisi_ptt *hisi_ptt;
> +	int target, src;
> +
> +	hisi_ptt = hlist_entry_safe(node, struct hisi_ptt, hotplug_node);
> +	src = hisi_ptt->trace_ctrl.on_cpu;
> +
> +	if (!hisi_ptt->trace_ctrl.started || src != cpu)
> +		return 0;
> +
> +	target = cpumask_any(cpumask_of_node(dev_to_node(&hisi_ptt->pdev->dev)));
> +	if (target < nr_cpumask_bits) {

the comment for cpumask_any() hints to check against nr_cpu_ids - any 
specific reason to check against nr_cpumask_bits?

> +		dev_err(hisi_ptt->hisi_ptt_pmu.dev, "no available cpu for perf context migration\n");
> +		return 0;
> +	}
> +
> +	perf_pmu_migrate_context(&hisi_ptt->hisi_ptt_pmu, src, target);
> +	WARN_ON(irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
> +				 cpumask_of(cpu)));
> +	hisi_ptt->trace_ctrl.on_cpu = target;
> +
> +	return 0;
> +}
> +
> +static int __init hisi_ptt_init(void)
> +{
> +	int ret;
> +
> +	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, DRV_NAME, NULL,
> +				      hisi_ptt_cpu_teardown);
> +	if (ret < 0)
> +		return ret;
> +	hisi_ptt_pmu_online = ret;
> +
> +	ret = pci_register_driver(&hisi_ptt_driver);
> +	if (ret)
> +		cpuhp_remove_multi_state(hisi_ptt_pmu_online);
> +
> +	return ret;
> +}
> +module_init(hisi_ptt_init);
> +
> +static void __exit hisi_ptt_exit(void)
> +{
> +	pci_unregister_driver(&hisi_ptt_driver);
> +	cpuhp_remove_multi_state(hisi_ptt_pmu_online);
> +}
> +module_exit(hisi_ptt_exit);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Yicong Yang <yangyicong@hisilicon.com>");
> +MODULE_DESCRIPTION("Driver for HiSilicon PCIe tune and trace device");
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h
> new file mode 100644
> index 000000000000..2344e4195648
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.h
> @@ -0,0 +1,178 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <yangyicong@hisilicon.com>
> + */
> +
> +#ifndef _HISI_PTT_H
> +#define _HISI_PTT_H
> +
> +#include <linux/bits.h>
> +#include <linux/cpumask.h>
> +#include <linux/list.h>
> +#include <linux/pci.h>
> +#include <linux/perf_event.h>
> +#include <linux/spinlock.h>
> +#include <linux/types.h>
> +
> +#define DRV_NAME "hisi_ptt"
> +
> +/*
> + * The definition of the device registers and register fields.
> + */
> +#define HISI_PTT_TRACE_ADDR_SIZE	0x0800
> +#define HISI_PTT_TRACE_ADDR_BASE_LO_0	0x0810
> +#define HISI_PTT_TRACE_ADDR_BASE_HI_0	0x0814
> +#define HISI_PTT_TRACE_ADDR_STRIDE	0x8
> +#define HISI_PTT_TRACE_CTRL		0x0850
> +#define   HISI_PTT_TRACE_CTRL_EN	BIT(0)
> +#define   HISI_PTT_TRACE_CTRL_RST	BIT(1)
> +#define   HISI_PTT_TRACE_CTRL_RXTX_SEL	GENMASK(3, 2)
> +#define   HISI_PTT_TRACE_CTRL_TYPE_SEL	GENMASK(7, 4)
> +#define   HISI_PTT_TRACE_CTRL_DATA_FORMAT	BIT(14)
> +#define   HISI_PTT_TRACE_CTRL_FILTER_MODE	BIT(15)
> +#define   HISI_PTT_TRACE_CTRL_TARGET_SEL	GENMASK(31, 16)
> +#define HISI_PTT_TRACE_INT_STAT		0x0890
> +#define   HISI_PTT_TRACE_INT_STAT_MASK	GENMASK(3, 0)
> +#define HISI_PTT_TRACE_INT_MASK		0x0894
> +#define HISI_PTT_TRACE_WR_STS		0x08a0
> +#define   HISI_PTT_TRACE_WR_STS_WRITE	GENMASK(27, 0)
> +#define   HISI_PTT_TRACE_WR_STS_BUFFER	GENMASK(29, 28)
> +#define HISI_PTT_TRACE_STS		0x08b0
> +#define   HISI_PTT_TRACE_IDLE		BIT(0)
> +#define HISI_PTT_DEVICE_RANGE		0x0fe0
> +#define   HISI_PTT_DEVICE_RANGE_UPPER	GENMASK(31, 16)
> +#define   HISI_PTT_DEVICE_RANGE_LOWER	GENMASK(15, 0)
> +#define HISI_PTT_LOCATION		0x0fe8
> +#define   HISI_PTT_CORE_ID		GENMASK(15, 0)
> +#define   HISI_PTT_SICL_ID		GENMASK(31, 16)
> +
> +/* Parameters of PTT trace DMA part. */
> +#define HISI_PTT_TRACE_DMA_IRQ			0
> +#define HISI_PTT_TRACE_BUF_CNT			4
> +#define HISI_PTT_TRACE_BUF_SIZE			SZ_4M
> +#define HISI_PTT_TRACE_TOTAL_BUF_SIZE		(HISI_PTT_TRACE_BUF_SIZE * \
> +						 HISI_PTT_TRACE_BUF_CNT)
> +/* Wait time for hardware DMA to reset */
> +#define HISI_PTT_RESET_TIMEOUT_US	10UL
> +#define HISI_PTT_RESET_POLL_INTERVAL_US	1UL
> +/* Poll timeout and interval for waiting hardware work to finish */
> +#define HISI_PTT_WAIT_TRACE_TIMEOUT_US	100UL
> +#define HISI_PTT_WAIT_POLL_INTERVAL_US	10UL
> +
> +#define HISI_PCIE_CORE_PORT_ID(devfn)	(PCI_FUNC(devfn) << 1)
> +
> +/* Definition of the PMU configs */
> +#define HISI_PTT_PMU_FILTER_IS_PORT	BIT(19)
> +#define HISI_PTT_PMU_FILTER_VAL_MASK	GENMASK(15, 0)
> +#define HISI_PTT_PMU_DIRECTION_MASK	GENMASK(23, 20)
> +#define HISI_PTT_PMU_TYPE_MASK		GENMASK(31, 24)
> +#define HISI_PTT_PMU_FORMAT_MASK	GENMASK(35, 32)
> +
> +/**
> + * struct hisi_ptt_dma_buffer - Describe a single trace buffer of PTT trace.
> + *                              The detail of the data format is described
> + *                              in the documentation of PTT device.
> + * @dma:   DMA address of this buffer visible to the device
> + * @addr:  virtual address of this buffer visible to the cpu
> + */
> +struct hisi_ptt_dma_buffer {
> +	dma_addr_t dma;
> +	void *addr;
> +};
> +
> +/**
> + * struct hisi_ptt_trace_ctrl - Control and status of PTT trace
> + * @trace_buf: array of the trace buffers for holding the trace data.
> + *             the length will be HISI_PTT_TRACE_BUF_CNT.
> + * @handle:    perf output handle of current trace session
> + * @buf_index: the index of current using trace buffer
> + * @on_cpu:    current tracing cpu
> + * @started:   current trace status, true for started
> + * @is_port:   whether we're tracing root port or not
> + * @direction: direction of the TLP headers to trace
> + * @filter:    filter value for tracing the TLP headers
> + * @format:    format of the TLP headers to trace
> + * @type:      type of the TLP headers to trace
> + */
> +struct hisi_ptt_trace_ctrl {
> +	struct hisi_ptt_dma_buffer *trace_buf;
> +	struct perf_output_handle handle;
> +	u32 buf_index;
> +	int on_cpu;
> +	bool started;
> +	bool is_port;
> +	u32 direction:2;
> +	u32 filter:16;
> +	u32 format:1;
> +	u32 type:4;
> +};
> +
> +/**
> + * struct hisi_ptt_filter_desc - Descriptor of the PTT trace filter
> + * @list:    entry of this descriptor in the filter list
> + * @is_port: the PCI device of the filter is a Root Port or not
> + * @devid:   the PCI device's devid of the filter
> + */
> +struct hisi_ptt_filter_desc {
> +	struct list_head list;
> +	bool is_port;
> +	u16 devid;
> +};
> +
> +
> +/**
> + * struct hisi_ptt_pmu_buf - Descriptor of the AUX buffer of PTT trace
> + * @length:   size of the AUX buffer
> + * @nr_pages: number of pages of the AUX buffer
> + * @base:     start address of AUX buffer
> + * @pos:      position in the AUX buffer to commit traced data
> + */
> +struct hisi_ptt_pmu_buf {
> +	size_t length;
> +	int nr_pages;
> +	void *base;
> +	long pos;
> +};
> +
> +/**
> + * struct hisi_ptt - Per PTT device data
> + * @trace_ctrl:   the control information of PTT trace
> + * @hotplug_node: node for register cpu hotplug event
> + * @hisi_ptt_pmu: the pum device of trace
> + * @iobase:       base IO address of the device
> + * @pdev:         pci_dev of this PTT device
> + * @pmu_lock:     lock to serialize the perf process
> + * @upper_bdf:    the upper BDF range of the PCI devices managed by this PTT device
> + * @lower_bdf:    the lower BDF range of the PCI devices managed by this PTT device
> + * @port_filters: the filter list of root ports
> + * @req_filters:  the filter list of requester ID
> + * @port_mask:    port mask of the managed root ports
> + */
> +struct hisi_ptt {
> +	struct hisi_ptt_trace_ctrl trace_ctrl;
> +	struct hlist_node hotplug_node;
> +	struct pmu hisi_ptt_pmu;
> +	void __iomem *iobase;
> +	struct pci_dev *pdev;
> +	spinlock_t pmu_lock;
> +	u32 upper_bdf;
> +	u32 lower_bdf;
> +
> +	/*
> +	 * The trace TLP headers can either be filtered by certain
> +	 * root port, or by the requester ID. Organize the filters
> +	 * by @port_filters and @req_filters here. The mask of all
> +	 * the valid ports is also cached for doing sanity check
> +	 * of user input.
> +	 */
> +	struct list_head port_filters;
> +	struct list_head req_filters;
> +	u16 port_mask;
> +};
> +
> +#define to_hisi_ptt(pmu) container_of(pmu, struct hisi_ptt, hisi_ptt_pmu)
> +
> +#endif /* _HISI_PTT_H */